test3.go

package main

import (
	"fmt"
	"strings"
	"github.com/tidwall/gjson"
)

func main() {
	jsonContent := `{"spu_id":2170358070290851004,"old_goods_id":17003294699,"update_time":1703580702,"cp_time":0,"goods_status":1,"goods_type":1,"supplier_id":5,"goods_name":"NFM21HC105R1C3D","encoded":"","batch_sn":"2310","moq":232,"mpq":1,"stock":3562,"hk_delivery_time":"","cn_delivery_time":"","ladder_price":[{"purchases":232,"price_cn":0,"price_us":0.1377,"cost_price":0},{"purchases":500,"price_cn":0,"price_us":0.1211,"cost_price":0},{"purchases":1000,"price_cn":0,"price_us":0.0961,"cost_price":0},{"purchases":2000,"price_cn":0,"price_us":0.0924,"cost_price":0}],"goods_images":"","canal":"","eccn":"EAR99","multiple":0,"source":2}`
	spu_id := gjson.Get(jsonContent,"spu_id").String()

	fmt.Println(spu_id)
	fmt.Println("ddddddddd")

	jsonContent = strings.Replace(jsonContent, spu_id, "\""+spu_id+"\"", 1)

	fmt.Println(jsonContent)

}